Deferasirox is chemically known as 4-[3,5-bis(2-hydroxyphenyl)-[1,2,4]triazol-1-yl]benzoic acid. It is a rationally-designed oral ironchelator. Its main use is to reduce chronic iron overload in patients who are receiving long-term blood transfusions for conditions such as beta-thalassemia and other chronic anemias. The current pharmaceutical product containing this drug is being sold by Novartis using the tradename Exjade® in the form of tablets.
U.S. Pat. No. 6,465,504 discloses a process for preparing Deferasirox wherein the process includes reacting salicyloyl chloride with salicylamide at 170° C. to obtain 2-(2-hydroxyphenyl)benz[e][1,3]oxazin-4-one, and further crystallization in ethanol to obtain slight yellow color crystals of 2-(2-hydroxyphenyl)benz[e][1,3]oxazin-4-one. 2-(2-hydroxyphenyl)benz[e][1,3]oxazin-4-one which is further reacted with 4-hydrazinebenzoic acid in presence of ethanol to give Deferasirox. Major drawback of this process is preparation of 2-(2-hydroxyphenyl)benz[e][1,3]oxazin-4-one at high temperature and in the absence of solvent which causes formation of several impurities which is difficult to avoid.
U.S. Pat. No. 6,465,504 disclose process for the preparation of Deferasirox which require unwieldy steps for the preparation and purification of Deferasirox. The reaction conditions employed for the production of Deferasirox results in formation of large amount of impurities.
WO2009/094956 disclose the process for preparing Deferasirox where in the process includes the reaction of 2-(2-hydroxyphenyl)benz[e][1,3]oxazin-4-one with 4-hydrazinebenzoic acid is carried out in the presence of organic acid such as C1 to C4 carboxylic acid.
Therefore, there is a need of process for the preparation of Deferasirox which not only devoid disadvantages of prior process as mentioned hereinabove but also gives high yield and purity of Deferasirox. The process of present invention overcomes disadvantages of prior process and gives high yield and purity of Deferasirox.